BELLWORK 4

WHAT IS THE MAIN IDEA?

Caffeine is a natural ingredient in coffee, cocoa, tea, and chocolate, and is added to some prescription and non-prescription drugs. 2. Despite being "natural," caffeine is also a powerful drug which greatly affects the body. 3. In healthy, rested people, a dose of 100 milligrams (about one cup of coffee) increases alertness, banishes drowsiness, quickens reaction time, it enhances intellectual and muscular effort, and increases heart and respiratory rates. 4. Drinking one to two cups of coffee an hour before exercise encourages the body to preserve glycogen and burn fat -----something that results in greater endurance. 5. In addition, caffeine masks fatigue. 6. In doses above 300 milligrams, caffeine can produce sleeplessness, nervousness, irritability, headaches, heart palpitations, and muscle twitches. 7. Caffeine is also habit-forming, and those who try to suddenly stop after heavy use may experience such withdrawal symptoms as headaches, lethargy, irritability, and difficulty in concentrating.The main idea of this passage is that caffeine.....

• a. is a powerful drug that affects the body in numerous ways.

• b. is good to drink before working out.

• c. is linked to various health concerns.

• d. is a strong drug that only enhances the body when used.